Method for molding cup-shaped bodies



y 1966 1.. J. GEHL 3,259,974

METHOD FOR MOLDING CUP-SHAPED BODIES Original Filed Aug. 18, 1961 2Sheets-Sheet 1 l 29 4 2J2 .23 2a INVENTOR. [A we ewes J 65:-

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July 12, 1966 L. J. GEHL METHOD FOR MOLDING CUP-SHAPED BODIES 2Sheets-Sheet 2 Original Filed Aug. 18, 1961 INVENTOR. [A NEEIVCE J65/11.

wmnma 19 TI'ORNEY United States Patent METHOD FOR MOLDING CUP-SHAPEDBODI ES Lawrence J. Geh], Corning, N.Y., assignor to Corning GlassWorks, Corning, N.Y., a corporation of New York Original applicationAug. 18, 1961, Ser. No. 132,335, now Patent No. 3,149,375. Divided andthis application Nov. 6, 1963, Ser. No. 326,317

3 Claims. (Cl. 29-527) This application is a division of my copendingapplication Serial No. 132,335 filed August 18, 1961, now US. Patent3,149,375.

This invention relates to the method of molding a unitary cup-shapedbody with wires comolded in and passing generally horizontally throughthe base of the body from an external side surface to the inside surfaceof the base.

Attempts to produce a satisfactory and economical housing forsemiconductor devices resulted in the design of a cup-shaped base inwhich a plurality of conducting lead wires were to be comolded in andextended horizontally through the sidewall of the base to form a unitarystructure, as disclosed in copending US. patent application Serial No.76,046, by William C. Smith, filed December 15, 1960, now Patent No.3,220,095. In manufacturing the comolded base and wires, it was desiredto make it from granular or powdered ceramic material, either vitreousor crystalline, and which is known to be an easily molded material.However, no known molding apparatus was found capable of being operatedto manufacture this cup-shaped base from powdered ceramic moldablematerial with horizontally comolded wires therein.

It is, accordingly, an object of this invention to provide a method forcomolding wires and powdered or granular moldable material to form aunitary cup-shaped body with the wires passing generally horizontallythrough the base of the body from an external side surface to the insidesurface of the base.

While the present invention is especially useful for molding the unitarycup-shaped articles from powdered ceramic material, it can also beemployed for forming a similar article from other suitable powdered orgranular material, such as metal, carbon and the like, when so desired.

The present invention may be best understood by refence to theaccompanying drawings wherein:

FIG. 1 is a fragmentary, sectional, front elevation of a preferredembodiment of a molding press assembly according to the presentinvention,

FIG. 2 is a sectional plan view of the open-top die block taken on line2-2 of FIG. 1,

FIG. 3 is a fragmentary vertical sectional of the mold assembly showingthe moldable material and wires at the beginning of the compressionstroke,

FIG. 4 is a fragmentary vertical section of the mold assembly showingthe molded material and wires at the end of the compression stroke.

Referring to FIGS. 1 and 2, the molding assembly comprises a die block 1with a vertical bore defined by the cylindrical wall 2. The top surface3 of die block 1 contains grooves 4 communicating with the verticalbore. An annular mold cavity is defined by the cylindrical wall 2 of thevertical bore, core member 5 and axially movable surrounding means, ortubular ram 6.

A threaded lower end of core member 5 extends through hollow structure7, formed in a conventional molding press frame (not shown), and isconnected to air cylinder 8. Air cylinder 8 is suitably mounted on thebase of the molding press frame (not shown). Adjustable nut 9 is mountedon the threaded portion of core member 5 pass- 3,259,974 Patented July12, 1966 ing through the hollow in structure 7. Nut 9 is adjusted toposition the top end of core member 5 at the bottom level of grooves 4when nut 9 is forced upwardly by air cylinder 8 and against surface 10on structure 7.

Adjustable nut 11 is also mounted on the threaded portion of core member5 passing through the hollow in structure 7, but below nut 9. If it isdesired to maintain core member 5 stationary during the compressionstroke, nut 11 is adjusted downward on core member 5 until nut 9 isforced against surface 10 and nut 11 is pressed against surface 12 ofstructure 7. Where it is desired to downwardly displace core member 5 alimited distance during the compression stroke, nut 11 is adjustedupwardly a suitable distance away from surface 12 when nut 9 is forcedagainst surface 10 by air cylinder 8. The latter position of nut 11 isindicated by the dotted line 13.

Tubular ram 6 has a rigidly connected tubular extension 14, whichsurrounds core member 5. An adjustable nut 15 is mounted on an upperthreaded portion of extension 14. Nut 15 normally rests on thecylindrical supporting structure 32, which surrounds extension 14 and isa portion of the molding press frame (not shown). The top end of tubularram 6 is normally positioned at an appropriate level below the top endof core member 5 by adjusting nut 15.

Tubular ram 6 and nut 15 are resiliently maintained in their normalposition by means of springs 16, which are arranged around support rods17. The upper ends of rods 17 are rigidly attached to the underside ofpress table 18, which rigidly holds die block 1 in its upper surface.The lower ends of rods 17 pass through holes in plate 19. Plate 19 isarranged around extension 14 and rests on the upper surface of nut 15.Springs 17 engage the bottom surface of press table 18 and the topsurface of plate 19, thereby urging nut 15 downwardly to its normal restposition.

Circular die member 20 has a passage therethrough defined by cylindricalwall 21, the diameter of which is the same as that of the vertical borein die block 1. .Die member 20 is arranged over top surface 3 of dieblock 1 so that cylindrical wall 21 is in register with cylindrical wall2. The passage in die member 20 provides increased mold cavity capacityfor moldable material to form the base of the cup-shaped body.

One convenient means of rigidly positioning die member 20 is provided bythe raised peripheral portion 22 on the top surface of die block 1.Raised portion 22 has a surface 23 adapted to receive and rigidlyposition die member 20 on top of recessed surface 3. However, it will berecognized by those skilled in the art that other suitable positioningmeans may be utilized if desired.

Plunger 24 comprises a conventional solid cylinder adapted to enter theupper part of the mold cavity, as defined by the passage in die member20, by conventional cam operating means (not shown) for compression of acharge of moldable material placed in the mold cavity.

When additional compression is desired in the annular portion of themold cavity, tubular ram 6 can be advanced upwardly simultaneously withthe downward advance of plunger 24 within the mold cavity. For thispurpose, adjustable nut 25 is mounted on the lower threaded portion ofextension 14. Conventional cam operated lever arms 26 engage the bottomsurface of nut 25 on two opposite sides to effect the upward movement ofram 6 during compression.

Means for ejecting the molded body rrom the mold cavity comprises anadjustable nut 27 mounted on the upper threaded portion of extension 14and conventional cam operated lever arms 28, the latter engaging thebottom surface of nut 27 on two opposite sides to effect the upwardmovement of ram 6 after the compression cycle is 7 means for effectingappropriate motions to plunger 24 and ram 6, and for timing the sequenceof the motions, may be substantially as taught in US. Patent 2,499,980.

The operation of the molding press assembly is best described inconnection with the novel comolding method for forming the abovedescribed unitary cup-shaped body. Initially, die member 20 is removedby suitable means (for example, it can be removed manually by providinga handle means on the top surface 29 of die member 20). Air cylinder 8is actuated to position the top of core member at the bottom level ofgrooves 4. Although core member 5 can be maintained stationary duringcompression, it is preferred to allow a small downward displacement byadjusting nut 11 upward an appropriate distance to a positionrepresented by dotted line 13. Nut 15 is adjusted to provide the properamount of fill space in the annular portion of the mold cavity that willyield the desired height of the compressed cup-shaped body. When it isdesired to give greater strength to the annular wall of the cup-shapedbody, lever arms 26 are connected to conventional cam operating means toprovide upward advancement of ram 6 during compression and nut isadjusted so that during compression the top end of core member 5 remainsthe desired distance above the top end of ram 6 to yield the desiredheight of the annular wall of the cup-shaped body.

The first step of the method consists of positioning straight pieces ofwire horizontally through radially spaced openings in the sidewall of anopen top mold and in a plane intermediate the top and bottom of thecavity formed by the mold. Thus, the straight pieces of wire are placedin grooves 4 and die member 20 is replaced on top of surface 3.

Next, the wire pieces are extended horizontally into the cavity so thattheir innermost ends rest on and are supported by the core member 5.This step may be conveniently performed simultaneously with the firststep by providing wire pieces of appropriate length to occupy the entirelength of grooves 4 from surface 23 and to extend onto the top surfaceof core member 5. When utilizing this method to produce a semiconductorhousing base as disclosed in the aforementioned application Serial No.76,046, the innermost ends of the wire pieces. resting on core member 5are suitably spaced apart as shown in the copending application.

When the positioning and extending of the wire pieces is completed, theentire mold cavity (including the annular portion) is filled with acharge of granular molding material by conventional means (for example,as shown in US. Patent 2,499,980) and customarily up to the levelofsurface 29. Then the charge of molding mate-. rial is compressedwithin the cavity and, preferably concurrently therewith, the portion ofthe wire pieces within the cavity are downwardly displaced so that theypass through the base of the cup-shaped body generally diagonally fromspaced points near the bottom edge of the external side surface of thebase to the inner surface of the base and thence flush with the innersurface.

The preferred concurrent compressing and displacing steps are bestunderstood by referring to FIGS. 3 and 4. At the beginning of thecompression stroke, as shown in FIG. 3, wire pieces are in their initialposition and the entire mold cavity is filled with granular moldablematerial 31. Plunger 24 is on the down stroke and is ust entering thepassage in die member 20. At this point,

' tubular ram 6 is just beginning its upward advancement.

FIG. 4 shows plunger 24 and ram 6 at the end of their compressionstrokes with the resultant compression of the moldable material 31 intoa cup-shaped body and with the concurrent displacement of the wirepieces 30 to the aforementioned generally diagonal position within the 7base of the body. In effecting the concurrent compression anddisplacement, core member 5 has been displaced downwardly to its lowerlimit as deter-mined by nut 11 and against the resilient upward pressureeffected by air cylinder 8. If the downward displacement of the wirepieces is not desired, core member S should be maintained stationary.

At the end of the compression stroke, the pressure effected by aircylinder 8 is released before plunger 24 is withdrawn to prevent coremember 5 from breaking,

through the central portion of the base of the cup-shaped body as aresult of the annular wall of the cup-shaped body sticking to the moldcavity Wall. Then plunger 24 whereby ram 6 is returned to its normalposition by; means of springs 16. Air cylinder 8 is again actuated,

to position the top of core member 5 at the bottom level of grooves 4.

While the foregoing method has been described with the use of aplurality of wire pieces 30, it will be appre ciated that only one wirepiece may be provided, if desired for any particular purpose. In thepreferred embodiment for producing a semiconductor housing base, asindicated by FIG. 2, three wire pieces, each spaced substantiallyradially from another one, are provided to be comolded in the unitarycup-shaped body.

The depth and width of grooves 4 are preferably proportioned to closelyfit the cross-sectional dimensions of the desired wire pieces used.

Any suitable combination of granular moldable material and metal oralloy can be used for the body and wire.

pieces, respectively. A preferred combination used for thesemi-conductor housing base is glass of the composi tion disclosed incopending US. patent application Serial powder, and platinum metal inthe form of flat thin wire.

It should be understood that the illustrated embodiments of theinvention may be varied in their details within the spirit of theinvention. Accordingly, it is intended that the scope of the presentinvention be limited only by the appended claims.

What is claimed is:

1. The method of molding a unitary cup-shaped body with at least onewire passingthrough the base of said body generally horizontally fromthe external side surface of said base to the inner surface of said baseand thence flush with said inner surface, which comprises positioning atleast one straight piece of wire horizontally through an opening in thesidewall of an open top mold intermediate the top and bottom of thecavity formed by said mold, extending the wire horizontally into saidcavity and supporting the innermost end thereof on the top surface of acentral core member in the lower part of said cavity forming an annularcavity portion beneath said wire, filling the mold cavity with a chargeof granular molding material and compressing the molding material withinsaid cavity.

2. The method of claim 1 wherein the compressing is effected byconcurrently exerting pressure downwardly from the top of said cavityand upwardly from the bottom of said annular cavity portion.

3. The method of molding a unitary cup-shaped body with a plurality ofsubstantially radially spaced wires passing through the base of saidbody generally diagonally from spaced points near the bottom edge of theexternal side surface of said base to the inner surface of said base andthence flush with said inner surface, which comprises positioning aplurality of straight pieces of wire horizontally through radiallyspaced openings in the sidewall of an open top mold and in a planeintermediate the top and 3,259,974 5 v 6 bottom of the cavity formed bysaid mold, extending the References Cited by the Examiner Wire pieceshorizontally into said cavity and supporting UNITED STATES PATENTS theinnermost ends thereof on the top surface of a resiliently, downwardlydisplaceable central core member in 2,166,205 7/1939 et the lower partof said cavity forming an annular cavity 5 2,256,769 9/1941 Amnfle 18-36portion beneath said Wire pieces, filling the mold cavity 2276380 3/1942Enghsh et a1 18 36 with a charge of granular molding material, andconcur- 21,758,183 8/1956 Canegauorently compressing the moldingmaterial within said cavity and displacing the portion of the Wirepieces therein down- JOHN CAMPBELL Pr'mary Examiner wardly to saidgenerally diagonal position. 10 P. M. COHEN, Assistant Examiner.

1. THE METHOD OF MODLING A UNITARY CUP-SHAPED BODY WITH AT LEAST ONEWIRE PASSING THROUGH THE BASE OF SAID BODY GENERALLY HORIZONTALLY FROMTHE EXTERNAL SIDE SURFACE OF SAID BASE TO THE INNER SURFACE OF SAID BASEAND THENCE FLUSH WITH SAID INNER SURFACE, WHICH COMPRISES POSITIONING ALEAST ONE STRAIGHT PIECE OF WIRE HORIZONTALLY THROUGH AN OPENING IN THESIDEWALLS OF AN OPEN TOP MOLD INTERMEDIATE THE TOP AND BOTTOM OF THECAVITY FORMED BY SAID MOLD, EXTENDING THE WIRE HORIZONTALLY INTO SAIDCAVITY AND SUPPORTING THE INNERMOST END THEREOF ON THE TOP SURFACE OF ACENTRAL CORE MEMBER IN THE LOWER PART OF SAID CAVITY FORMING AN ANNULARCAVITY PORTION BENEATH SAID WIRE, FILLING THE MOLD CAVITY WITH A CHARGEOF GRANULAR MOLDING MATERIAL AND COMPRESSING THE MOLDING MATERIAL WITHINSAID CAVITY.